The present invention is directed to a method and system for modeling and simulating transmission lines. More specifically, the method and system serve to adaptively model and simulate lossy multi-conductor transmission lines representing conductive interconnections in a circuit layout, depending on the particularities of a given application. The method and system thereby provide for simulation and evaluation of transmission line transient behavior with an optimal combination of accuracy and, efficiency, even in high speed applications.
With recent advances in IC fabrication technology, and the ongoing development of computer and telecommunication systems, electronic designs operating at higher frequencies are becoming more prevalent. Data rates on the order of multi-Gbit/s, for instance, are not uncommon. In these applications, physical circuit interconnections such as conductive etches extending between neighboring components on a printed circuit board (PCB) cannot be modeled simply as ideal short-circuited point-to-point connections. At high operational frequencies, an interconnection is greater in its physical length than the transmitted signal's effective electrical length. There is generally a heightened sensitivity to transients and other factors which might otherwise be negligible, making a more precise modeling approach essential. Physical interconnections are therefore typically modeled as distributed transmission lines in high speed applications.
A distributed transmission line may impact the timing and integrity of transmitted signals through such factors as intrinsic propagation delay, skin effect, reflection, crosstalk, and the like. Thus, in order to verify that a high-speed design meets required timing and noise margins, there is a need for efficient and accurate measures by which to model and simulate lossy multi-conductor transmission lines.
While numerous simulation techniques are known in the art, there is still a need for an efficient and accurate modeling and simulation approach for lossy transmission lines, in particular for lossy multi-conductor transmission lines. There remains a need for such approach, whereby reliable simulation may be realized even in high frequency dependent environments, within broad operational frequency ranges.